Photointerrupter

Abstract

In a photointerrupter provided with a resin-molded single package, emitter leads for a light emitting element and a detector leads for a light detecting element are disposed substantially on the same plane so that the light emitting element and the light detecting element are disposed in side-by-side relationship. Preferably, the emitter leads and the detector leads are derived from the same plane of the resin-molde package, and all the leads are arrayed on a straight line like a single in-line package device.

What is claimed is: 
     
       1. A photointerrupter comprising: a first flat lead member having a first lead-out portion elongating substantially in a first direction and a first element mounting portion extending from one end of said first lead-out portion in a second direction substantially perpendicular to said first direction, said first element mounting portion having a major flat surface which is in parallel with a surface of said first lead-out portion and is positioned in a level lower than said surface of said first lead-out portion, a second flat lead member disposed on such side of said first flat lead member that said first element mounting portion is extended and having a second lead-out portion elongating substantially in said first direction and a second element mounting portion extending from one end of said second lead-out portion in said second direction toward said first element mounting portion, said second element mounting portion having a major flat surface which is in parallel with a surface of said second lead-out portion and is positioned in a level lower than said surface of said second lead-out portion, said major flat surface of said second element mounting portion and said major flat surface of said first element mounting portion being substantially in the same level, each of said first and second flat lead members having a reflective stair wall portion between the major flat surface of its element mounting portion and the surface of its lead-out portion, a third flat lead member disposed between said first and second lead members and having a third lead-out portion elongating along said first lead-out portion and substantially in said first direction and a first wire-bonding portion at one end of said third lead-out portion located adjacent to said first element mounting portion such that said first wire-bonding portion is spaced apart from said first element mounting portion in said first direction, a fourth flat lead member disposed between said second and third lead members and having a fourth lead-out portion elongating along said second lead-out portion and substantially in said first direction and a second wire-bonding portion at one end of said fourth lead-out portion located adjacent to said second element mounting portion such that said second wire-bonding portion is spaced apart from said second element mounting portion in said first direction, all of said first, second, third and fourth lead members being disposed substantially on the same plane, a light emitting element mounted on said major flat surface of said first element mounting portion such that one side end of said light emitting element is opposed to said reflective wall of said first lead member, a first bonding wire electrically connecting said light emitting element to said first wire-bonding portion, a light detecting element mounted on said major flat surface of said second element mounting portion such that one side end of said light detecting element is opposed to said reflective stair wall portion of said second lead member, a single packaging member commonly encapsulating said first, second, third and fourth lead members and said light emitting and light detecting elements such that a gap is formed between said first element mounting portion and second element mounting portion, a first convex lenses disposed between said first element mounting portion and said gap, and a second convex lenses disposed between said second element mounting portion and said gap, said first and second convex lenses being adapted to transfer the light emitted from the side end of said light emitting element to the side end of said light detecting element. 
     
     
       2. A photointerrupter, comprising: a light emitting element mounted on an element mount surface of a first lead and connected electrically to a second lead,   a light detecting element mounted on an element mount surface of a third lead and connected electrically to a fourth lead, each of said light emitting element and light detecting element having a pair of major surfaces and side surfaces extending therebetween, one of said major surfaces being mounted on one of said element mount surfaces, and   a resin package commonly molding said light emitting element and light detecting element with said element mount surfaces of said first and third leads, both of said element mount surfaces being arranged substantially on the same plane, all of said first, second, third and fourth leads being supported only by said package and arranged in parallel on said plane and derived from one end surface of said package, said package having a slit to provide a predetermined air gap between said light emitting element and light detecting element, said package further having a pair of lenses provided on opposing walls of said slit such that the light emitted from said side surface of said light emitting element is directed mainly to said side surface of said light detecting element, through said air gap, said pair of lenses and said package being commonly formed by the same material which is transparent to the light emitted from said light emitting element.   
     
     
       3. A photointerrupter, comprising: a light emitting element mounted on an element mount surface of a first lead and connected electrically to a second lead,   a light detecting element mounted on an element mount surface of a third lead and connected electrically to a fourth lead,   a single resin-molded package commonly housing said light emitting element and light detecting element with said first, second, third and fourth leads, said package having a slit of a predetermined air gap between said light emitting element and said light detecting element, said first, second, third and fourth leads being supported only by said package and positioned substantially on the same plane and derived from said package, said package further having a pair of convex lenses respectively provided on opposing walls of said slit, said element mount surfaces of said first and third leads being extended along said plane within said package so that the principal surfaces of said light emitting element and said light detecting element are arranged in side-by-side relationship and thereby directing the light emitted from the side end of said light emitting element toward the side end of said light detecting element through said air gap and convex lenses.   
     
     
       4. The photointerrupter as claimed in claim 3, wherein said first, second, third and fourth leads are all derived from the same plane of said package, and said all leads are arrayed on a straight line. 
     
     
       5. The photointerrupter as claimed in claim 3, wherein said element mount surfaces of said first and third leads are depressed to form stair walls for reflection. 
     
     
       6. A photointerrupter comprising: a light emitting element mounted on an element mount surface of a first lead and connected electrically to a second lead, a light detecting element mounted on an element mount surface of a third lead and connected electrically to a fourth lead, a single resin-molded package commonly housing said light emitting element and light detecting element with said first, second, third and fourth leads, said package having a slit of a predetermined air gap between said light emitting element and said light detecting element, said first, second, third and fourth leads being positioned substantially on the same plane and derived from said package, said element mount surfaces of said first and third leads being depressed to form stair walls for reflection and being extended along said plane within said package so that the principal surfaces of said light emitting element and said light detecting element are arranged in side-by-side relationship and thereby coupling the light emitted from the side end of said light emitting element to the side end of said light detecting element through said air gap.